Number of positive lymph nodes and lymphatic invasion are significant prognostic factors after pancreaticoduodenectomy for distal cholangiocarcinoma

Background: Early recurrence of distal cholangiocarcinoma (DCC) may result in a poorer prognosis. This study aimed to evaluate the clinicopathological factors that predict survival and recurrence in patients with DCC. Methods: Fifty-five patients with DCC who underwent pancreaticoduodenectomy between 2005 and 2015 were studied retrospectively. The following clinicopathological parameters were analyzed as predictors of disease-free survival (DFS) and overall survival (OS): sex, age, body mass index, presence of biliary tract decompression, macroscopic type, histological type, tumor size, TNM classification, lymph node metastasis ratio, number of positive lymph nodes (PLNs), lymphatic invasion, venous invasion, perineural invasion, proximal bile duct margin, dissected margin, portal system invasion, arterial system invasion, stage, and residual tumor. Results: Univariate analysis showed that contiguous extension of the primary tumor, PLN, lymphatic invasion, venous invasion, perineural invasion, and stage were significant prognostic factors for DFS and OS. Multivariate analysis revealed that PLN and lymphatic invasion were prognostic for DFS and OS (P<0.001). Significant differences in OS and DFS were found in analyses stratified by PLN (0, 1, 2 vs ≥3) and lymphatic invasion (0 vs 1, 2, 3). Conclusion: Among the clinicopathological parameters analyzed, PLN and lymphatic invasion were confirmed as prognostic factors for DCC.